Leaf-miner: An initial gallery, which usually follows the leaf margin. Then
forms a blotch, mining from the leaf base to the tip. The presence
of a pupa in the mine is unusual for this species and may indicate
parasitism (British
leafminers).

Oviposition
on the leaf underside. The mine begins as a long corridor with a
very broad, green frass line. This corridor suddenly widens into
a broad blotch, that in the end may occupy almost an entire leaflet.
The blotch generally begins in the leaf base, and it is here that
most frass is concentrated. Shortly before pupation the larva leaves
its mine through an exit slit in the lower epidermis. After the
mine has been vacated the leaflet drops off (Bladmineerders van Europa).

Larva: The larvae of moths have a head capsule and chewing mouthparts with opposable mandibles (see video of a gracillarid larva feeding), six thoracic legs and abdominal legs (see examples).

The
larva is pale yellow, looks green in the mine; it lies dorsum upwards.
The larva is described by Johansson et al. (1990a); thorax dorsally
with 13, 11, and 9 pairs of setae per segment, respectively (Bladmineerders van Europa).

Pupa: The pupae of moths have visible head appendages, wings and legs which lie in sheaths (see examples).

Distribution
in Great Britain and Ireland: Britain including Cardiganshire, Carmarthenshire, Dorset, East Suffolk, Glamorgan, North Essex, North Somerset, Shropshire, South Hampshire, South-west Yorkshire and West Norfolk (NBN
Atlas).